The present invention relates to an ammunition unit of the type including a front ammunition component including a projectile that extends to the bottom of the ammunition component and a rear ammunition component including a casing bottom and a propelling charge igniter that extends axially essentially over the length of the rear ammunition component, with each of the two ammunition components including a combustible propelling charge casing. Still more particularly, the present invention relates to an ammunition unit of the above type wherein the front ammunition component is provided with a cylindrical charge casing section which is filled with propelling charge powder, the rear ammunition component is filled with propelling charge powder that has been compressed into a compressed member, and a supplemental charge is disposed, if required, in the region between the two ammunition components.
A two-part ammunition unit of the above type is disclosed in European Published application EP-OS 0,429,753 corresponding to U.S. Pat. No. 5,133,240. In this ammunition unit, a forward ammunition component accommodates a fin stabilized kinetic energy projectile in a propelling charge casing that is filled with bulk propelling charge powder, while the propelling charge casing of the adjacent rear ammunition component is filled with compressed propelling charge powder. A firing tube provided with openings is screwed into the casing bottom. The middle contact region between the two components is closed by a combustible covering disk. The total charge density that can be realized here is not particularly great if tail components of the projectile (propelling cage and guide mechanism) extend far into the cartridge, and therefore the rear ammunition component that is worked to hold the compressed propelling charge powder must be correspondingly small. Moreover, after a round has been fired, the ignition tube projects beyond the casing bottom while the propelling charge casings combust down to the casing bottom. Although it is possible that the front ammunition component may be filled, if required, with compressed propelling charge powder instead of bulk propelling charge powder, this is very expensive to produce.
Moreover, Federal Republic of Germany Laid-Open Patent application No. DE-OS 4,041,611, corresponding to allowed U.S. patent application 07/809,128, filed Dec. 8, 1991, discloses an ammunition unit in which a fin stabilized kinetic energy projectile including a propelling cage (sabot) is accommodated by a separate front ammunition component, with the fins of the projectile extending to the bottom of the front ammunition component. The latter accommodates tubular propelling charge powder in a propelling charge casing in the region of the fins, and bulk propelling charge powder in the region of the propelling cage (sabot). The separate rear ammunition component includes a propelling charge casing that is filled with bulk propelling charge powder in which a propelling charge igniter is disposed that extends axially over the length of the rear ammunition component. The resulting charge density is not particularly great.
In addition, Federal Republic of Germany Laid-Open patent application No. DE-OS 2,648,137 corresponding to U.S. Pat. No. 4,770,099 discloses a propelling charge igniter for ammunition in which a breech ring is provided that can be screwed into the casing bottom of an ammunition unit so as to accommodate a combustible firing tube for an ignition charge. However, such propelling charge igniters cannot be sufficiently secured in bulk propelling charge powder, so that they cannot ensure the formation of uniform gas pressure curves. Moreover, they may even break off, which would lead to safety risks.
European Patent No. 0,304,099, corresponding to U.S. Pat. No. 4,876,962 and European Patent No. 0,304,100, corresponding to U.S. Pat. No. 4,911,077 disclose a propelling charge comprising a bundle of densely packed tubes or rods of propelling charge powder (tubular powder) that extend practically over the entire length of the cartridge. The tubes or rods are provided with transverse slots and have axial channels as well as intended break locations. This bundle of tubes may be surrounded by bulk propelling charge powder. Drives made of such tube bundles do not realize the charge densities of a compacted charge.